KR100412419B1 - Method of preparing acrylate grout solution for grouting - Google Patents

Abstract

The present invention can be very effectively used as an injection chemical of the chemical injection method for the purpose of indexing the joints and cracks of underground structures and concrete structures to prevent the inflow or outflow of groundwater in civil engineering and building construction The present invention relates to a method for preparing an acrylate-based injection chemical of a new composition which is a new injection chemical. Injectable chemical solution according to the present invention has the advantage of eliminating the disadvantages of the conventional injectable chemical solution is excellent in the general engineering properties as a grouting material such as gel permeability coefficient, viscosity, gel time control.

Description

Method for preparing acrylate-based injection liquid for ground injection {Method of preparing acrylate grout solution for grouting}

The present invention relates to a method for preparing an acrylate-based injection liquid for ground injection, more specifically, to joints, cracks, and the like of underground structures and concrete structures to prevent the inflow or outflow of groundwater in civil engineering and building construction. The present invention relates to a method for preparing an acrylate-based injection chemical solution for ground injection, which can be used very effectively as an injection chemical solution for a chemical injection method for the purpose of indexing a part.

Grouting injection liquids that have been used conventionally are classified into inorganic chemical liquid systems such as sodium silicate (water glass), polymer chemicals such as phenol resin, chromium-lignin, epoxy, acrylamide, and urethane. It is common to select and construct an appropriate injection material in consideration of the advantages and disadvantages of each injection material considering the injection purpose and injection environment. Among the various injection materials described above, the most widely used is sodium silicate because of its low cost, relatively good workability, and extremely low environmental pollution. In the case of other injection materials, its use is relatively limited, which is a problem in terms of performance as an injection material, but is due to an external performance problem, which is expensive or harmful, and thus is used only in special conditions. It's a situation.

Sodium silicate-based injection material, which is used the most, has the advantages of relatively good workability, less pollution and good economical efficiency as described above, but it is lost by groundwater after a certain time due to poor durability of the gel solidified into the ground. In addition, since the viscosity of the injectable drug solution has a great influence on the injection performance, the injectable drug solution having a lower viscosity improves the injection performance, whereas the soda silicate-based injection solution has a relatively high viscosity, which limits the injectability. This limits the scope of application.

On the other hand, in the above-mentioned other injection chemical solution, the acrylamide injection chemical solution is mixed with the crosslinking agent to dissolve the acrylamide monomer to make an aqueous solution, and by adding an appropriate catalyst to the ground, it is injected into the ground to induce a chain polymerization reaction. It is a chemical solution used as an injection material by changing to hydrogel in a hydrous state. This chemical solution is very easy to inject due to its low viscosity and can freely adjust the curing time. It also has excellent durability of the gel, so that it does not dissolve by groundwater, and it has excellent engineering characteristics such as strength and permeability coefficient. Since there is no change in physical properties and can be said to be a very good ground injection material, it has been evaluated as the best injection material among all conventional ground injection materials. However, acrylamide has a relatively high toxicity of monomers, so it may be contaminated with groundwater, requiring attention on use, and its use is currently limited.

Accordingly, there has been a need for an injection material that has excellent engineering properties (excellent injectability, durability, etc.) and little harmful effects, such as acrylamide injection chemical solution. Its physical properties are known to be similar to acrylamide-based chemicals but with much less hazard. It is known that some developed countries have already developed and used this series of injection chemicals, but the exact composition and preparation method of the injection chemicals are not known in detail.

Therefore, the present inventors have repeatedly conducted research to independently develop a method for preparing an acrylate-based chemical solution, which is more suitable for use as a ground injection chemical and can be manufactured from a raw material having excellent physical properties and easily obtained. As a result, a method for preparing an acrylate-based chemical liquid which can be manufactured through an economical manufacturing process while having excellent mechanical properties has been developed, and the present invention has been completed based on this.

Therefore, the object of the present invention is very good injectability, and the gel permeation coefficient of the resulting gel is not only very low, but also easy to control the gel time, so the performance as a ground injection material for order and index is very excellent, the conventional grouting method The present invention provides a method for preparing an acrylate-based injectable chemical solution for ground injection that exhibits a turbid infusion effect in situations and conditions that are difficult to achieve.

The production method of the present invention for achieving the above object is adjusted to pH 7 to 8 by dropwise addition of an aqueous acrylic acid monomer solution to the inorganic base aqueous solution, and added to the polymerization crosslinking agent of 1 to 10% by weight based on the acrylic acid monomer concentration Providing an acrylate monomer aqueous solution in a range of 3 to 50% by weight; Providing a first sample in which a reduction catalyst or an oxidation catalyst is added to a predetermined solution of the aqueous monomer solution in an amount of 0.1 to 5% by weight based on the solid solution of the monomer solution; Providing a second sample in which the same amount of the reducing catalyst or the oxidation catalyst and the catalyst used in the first sample are added to the other aqueous monomer solution or water in the same amount as the aqueous monomer solution used in the preparation of the first sample. ; And mixing the first sample and the second sample at a time.

Looking at the present invention in more detail as follows.

The acrylate-based injection liquid according to the present invention is characterized by preparing a reaction mother liquor, which is an aqueous solution of an acrylate-based metal salt of a specific chemical component, and mixing it with an appropriate catalyst and other additives through an appropriate mixing process to induce a chain polymerization reaction to gel it. do.

First, the method for preparing a monomer aqueous solution is described, wherein a single or two or more acrylic organic acids selected from acrylic acid, methacrylic acid and 3,3-dimethyl acrylic acid are selected from sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide and calcium hydroxide. A single or two or more kinds of inorganic bases are mixed and reacted at an appropriate ratio to prepare an acrylic acid metal salt aqueous solution as a polymerization monomer, and N, N'-methylenebisacrylamide is added and dissolved as a crosslinking agent to prepare a polymerization monomer mother liquid. Manufacture. Next, triethanolamine (TEA), diethanolamine (DEA), nitrilo-tris-propionamide (NTP), and dimethylaminopropionitrile (DMAPN), which are redox catalysts selected as chain polymerization catalysts. Add at least one substance selected from and ammonium persulfate, at least one substance selected from sodium persulfate, potassium ferricyanide (KFeCN), a reaction retardant, and other additives for controlling physical properties through a separate compounding process according to the present invention. By mixing it, it can be induced into the curing process. In the curing process, the reaction is initiated by the oxidation / reduction reaction catalyst component, and N, N'-methylenebisacrylamide (MBAA) used as an acrylic acid metal salt and a crosslinking agent causes a chain polymerization reaction, so that the amount of the catalyst and the reaction delay agent is large and small. To crosslinked polymers of acrylic acid metal salts over a few seconds to several hours. It is an insoluble water swellable polymer and has the characteristic of being cured as a hydrogel with water initially included. The gel thus formed forms a colorless to yellow transparent to translucent flexible gel. Therefore, by using the gelling property, the mixed acrylate-based chemical solution according to the present invention is mixed with the ground, which requires the order or index of groundwater, cracks, gaps, or joints of concrete structures. You will be able to play a role.

Meanwhile, the constituents and the preparation method of the aqueous monomer solution of the acrylate-based injection drug solution according to the present invention will be described in detail. First, a single or selected from sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide and calcium hydroxide in an appropriate amount of distilled water; A solution of inorganic base is prepared by adding and dissolving two or more inorganic bases in a predetermined amount to induce an acid-base neutralization reaction by adding a certain amount of single or two or more acrylic organic acids selected from acrylic acid, methacrylic acid and 3,3-dimethyl acrylic acid. do. At this time, since an exothermic phenomenon occurs, the organic acid is slowly added dropwise, and an appropriate cooling device and a reflux device are used to prevent the liquid from overheating and evaporating. Thereafter, an appropriate amount of N, N'-methylenebisacrylamide (MBAA) is added thereto to dissolve, which is not dissolved in cold water, so it is preferable to dissolve while maintaining the temperature at 30 to 40 ℃. The concentration of the solid content of the aqueous monomer solution prepared in this way is preferably adjusted in the range of 3% to 50% by weight. On the other hand, the viscosity of the acrylate monomer mother liquor prepared in this way was measured, it was confirmed that it is in the range of 2 to 4 centipoise depending on the concentration of the monomer at 20 ℃.

The acrylic acid, methacrylic acid, and 3,3-dimethyl acrylic acid used as raw materials for the monomers described above vary in the physical properties of the gel formed after the reaction depending on which one is selected. 3,3-dimethyl acrylic acid <methacrylic acid < The gel that is finally formed in the order of acrylic acid has stronger and more resilient properties, whereas in the reverse order, a flexible and sticky gel is formed. Therefore, a gel having desired physical properties can be obtained by mixing and using the aforementioned three monomers in an appropriate ratio. In addition, the physical properties of the resulting gel also change depending on the total monomer concentration in the aqueous monomer solution to be prepared. The higher the concentration of the monomer, the stronger the gel is formed, but if the concentration is too high, the heat of the polymerization increases, so that the hydrogel Sudden overheating leads to poor results such as gel rupture. On the contrary, if the monomer concentration is too low, the gel is not formed and ends in a grassy state. Therefore, the appropriate concentration range of the final monomer concentration is in the range of 3% to 50% by weight in an aqueous solution, it can be adjusted freely within this range.

Meanwhile, in the inorganic base aqueous solution prepared before the addition of the acrylic acid monomer, the inorganic base is selected from sodium hydroxide, potassium hydroxide, lithium hydroxide, magnesium hydroxide, and calcium hydroxide, wherein the amount of magnesium hydroxide, calcium hydroxide, etc. increases later. The gel formed by the polymerization process has a stronger and more elastic gel. On the other hand, when the amount of sodium hydroxide, potassium hydroxide and lithium hydroxide is increased, a more flexible and sticky gel is formed. It is good to add a good combination of amounts. On the other hand, the amount of addition of these inorganic bases is neutralized with the acrylic organic acid added to it in the future to adjust the acidity (pH) of the final solution to a neutral region of 7 to 8 so as to adjust in advance so that the free base does not exist in the aqueous solution. It features.

In addition, the amount of N, N'-methylenebisacrylamide (MBAA) added as the polymerization crosslinking agent is preferably 1% to 10% by weight relative to the amount of the acrylic acid monomer, but if less than 1%, the final product It does not become a gel and becomes a highly viscous sol or a gel that is too flexible and unsatisfactory. On the other hand, when 10% or more is added, the resulting gel has a high strength but is weak due to being broken by impact. This is because the physical properties are not satisfactory.

Hereinafter, a process and an addition method of deriving the aqueous solution of the aqueous solution containing the acrylic acid-based metal salt and the crosslinking agent prepared as described above by gelation using an appropriate curing reaction catalyst and other additives will be described.

As a polymerization catalyst for gelation, a water-soluble oxidation / reduction catalyst may be used. However, in the present invention, as a reduction catalyst (A catalyst), triethanolamine (TEA), diethanolamine (DEA), nitrilo-tris-propionamide ( NTP) and at least one amine organic base catalyst selected from dimethylaminopropionitrile (DMAPN) was used, and at least one persulfate catalyst selected from prop persulfate and ammonium persulfate as the oxidation catalyst (B catalyst). You can get good results with

The addition of these catalysts can be performed in various ways. The first method takes two ((a) and (b)) in the same aqueous solution of the mixed acrylic organic acid metal salt monomer + crosslinking agent (MBAA) prepared as described above. To this, only a reduction catalyst (A catalyst) is added, and (B) only an oxidation catalyst (B catalyst) is added and mixed well, respectively, and then the two ((A) and (B)) are mixed. In the second method, only one of a reduction catalyst (A catalyst) or an oxidation catalyst (B catalyst) is added to the above-described aqueous solution of an acrylic organic acid metal salt monomer + crosslinking agent (MBAA) and the remaining catalyst (reduction catalyst (A catalyst) in separate pure water is added. ) Is added to the mother liquor, the oxidation catalyst (catalyst B) and the oxidation catalyst (catalyst B) are added to the mother liquor to prepare a single catalyst solution by dissolving the mother catalyst and the single catalyst solution. In this case, only one of the catalysts to be added to the mother liquor and the monocatalyst solution may be selected, and gelation may be induced through biphasic methods, which may be applied regardless of whether the catalyst is a reduction catalyst or an oxidation catalyst. It will be said that the characteristics of the application of the acrylate infusion drug solution according to the present invention.

On the other hand, a reduction catalyst (A) selected from triethanolamine (TEA), diethanolamine (DEA), nitrilo-tris-propionamide (NTP), and dimethylaminopropionitrile (DMAPN) used as the oxidation / reduction catalyst described above. Catalyst) and an oxidation catalyst (B catalyst) selected from sodium persulfate and / or ammonium persulfate, respectively, to the total amount of the addition amount of the acrylic acid monomer and the N, N'-methylenebisacrylamide (MBAA) crosslinking agent in the monomer mother liquor. It is characterized in that 0.1% to 5% by weight relative to the addition, it can be adjusted freely within the above range. If the amount of catalyst is increased, the reaction time is faster, and gelation occurs within 5 seconds after the reaction. On the contrary, if the amount of catalyst is decreased, the gelation time is delayed to several hours. This may not proceed at all.

In addition, potassium ferricyanide, which may be added separately if a reaction delay is required, may be delayed to gelation due to polymerization of the monomer for a predetermined time by using 1,000 ppm or less based on the weight of the aqueous monomer solution. When the amount is larger than the reduction catalyst, the reaction does not proceed at all. Its addition method is possible according to the method of addition of the catalyst described above, and it does not have any effect even if it is directly added to the mother liquor, a single catalyst aqueous solution, or both, but it is only necessary to consider the total amount added. .

In addition, additives for freezing prevention and dry shrinkage reduction may be added to control the properties of the hydrogel produced after gelation. For this purpose, additives such as glycerin, ethylene glycol, calcium chloride, and sodium chloride may be used alone or in combination. If the proper amount is added, the freezing is suppressed to -10 ° C. so that the gel can be kept soft and the drying and shrinkage due to moisture evaporation in the exposed part can be suppressed. The addition method can be added to the monomer mother liquid and the separate catalyst aqueous solution according to the case of the addition of the catalyst and the reaction delay agent described above, and the addition amount can be used in the range of 0.5 to 10% of the total liquid mixture. If the amount is too small, such as less than the range, the effect is almost disappeared, if too large, the physical properties of the gel is reduced.

Meanwhile, the acrylate-based injection liquid according to the present invention can be mixed with cement as an additional reinforcing additive material, and the application thereof can be performed through the following process.

(1) A predetermined amount of the acrylic acid-based metal salt monomer mother liquor according to the present invention is added thereto, and a predetermined amount of a catalyst selected from sodium persulfate and ammonium persulfate, which is an oxidation catalyst as part of the oxidation / reduction catalyst, is added thereto to dissolve it, and if necessary, the reaction delay. First, an additive such as a shrinkage reducing agent is added to prepare an aqueous solution (A liquid).

(2) Also, after mixing and dispersing a certain amount of ordinary cement or slag cement in separate pure water well, triethanolamine (TEA), diethanolamine (DEA), and nitrilo-tris-propionamide (NTP) And at least one amine-based organic base catalyst selected from dimethylaminopropionitrile (DMAPN) and mixed to prepare a reduction catalyst + cement dispersion aqueous solution (B solution).

(3) When the two liquids A and B thus prepared are mixed and stirred, a reaction occurs between the two liquids, and a cement / acrylate complex hydrogel is formed after a certain time. The characteristics of the gel are homogels with a simple acrylate solution. Compared with the properties of, the strength is improved, but the permeability coefficient shows similar characteristics.

As described above, the injection solution of the acrylate-based injection liquid according to the present invention has various application ranges, that is, 1) a mixed injection of a mother liquor containing only one of the oxidation and reduction catalysts + a mother liquid containing the other of the oxidation and reduction catalysts, 2) mixed injection of a monomer mother liquid containing only one of the oxidation and reduction catalysts + a pure catalyst liquid containing only one other of the oxidation and reduction catalysts, and 3) a monomer mother liquid containing an oxidation catalyst and a cement dispersion solution containing a reduction catalyst. It can be used as a ground injection chemical that can play a role of blocking water, reinforcing the ground and ordering and indexing by injecting into the ground through a two-component mixed injection method through a suitable injector in the same way as a mixed injection.

Hereinafter, the present invention will be described in more detail with reference to the following examples, and the present invention is not limited to the embodiments, which can be variously applied within the scope of the above description.

Example 1

To an aqueous solution of 30% by weight of sodium hydroxide and potassium hydroxide (molar ratio 1: 1), 50% by weight of acrylic acid and methacrylic acid (molar ratio 2: 1) aqueous solution is slowly added dropwise and stirred until the pH reaches about 7. It was. When it is confirmed that there is no change in pH after the dropwise addition, N, N'-methylenebisacrylamide corresponding to 3% by weight is added as a crosslinking agent to the mixed solution of acrylic acid and methacrylic acid already added dropwise, mixed, stirred and dissolved uniformly. An aqueous solution of acrylate monomer solution was prepared. From the monomer mother liquor prepared in this way, two samples were taken separately, 300 g each, 3 g of triethanolamine was added to one side, and 3 g of sodium persulfate was added to the other to dissolve. Stirred.

Example 2

Except for preparing a monomer mother liquor using 3,3-dimethyl acrylic acid instead of methacrylic acid was tested in the same manner and conditions as in Example 1.

Example 3

Experiments were conducted in the same manner and in the same manner as in Example 1, except that the monomer mother liquor was prepared using magnesium hydroxide instead of potassium hydroxide.

Example 4

N, N'-methylenebisacrylamide as a crosslinking agent was tested in the same manner and in the same manner as in Example 1 except that the monomer mother liquor was prepared using an amount equivalent to 2% by weight based on the acrylic acid and methacrylic acid mixture.

Example 5

Except for the addition of potassium ferricyanide in an amount corresponding to 100ppm to the entire monomer mother liquor prepared in Example 1 was tested in the same manner and conditions as in Example 1.

Example 6

To an aqueous solution of 30% by weight of sodium hydroxide and potassium hydroxide (molar ratio 1: 1), 50% by weight of acrylic and methacrylic acid (molar ratio 2: 1) aqueous solutions were slowly added dropwise and stirred until the pH reached about 7. It was. When it is confirmed that there is no change in pH after the dropwise addition, N, N'-methylenebisacrylamide corresponding to 3% by weight is added as a crosslinking agent to the mixed solution of acrylic acid and methacrylic acid already added dropwise, mixed, stirred and dissolved uniformly. A mother aqueous solution is prepared. 300 ml of the monomer mother liquid thus prepared is taken, and Solution A to which 3 g of triethanolamine is added is prepared. Separately, 300 ml of pure water was taken, and 3 g of ammonium persulfate was added thereto to prepare a solution B. The prepared solution A and solution B were mixed and stirred at a time.

Example 7

To the 1000 parts by weight of 30% by weight sodium hydroxide and potassium hydroxide (molar ratio 1: 1) aqueous solution of 50% by weight acrylic acid and methacrylic acid (molar ratio 2: 1) was slowly added dropwise and stirred until the pH reached about 8. It was. When it is confirmed that there is no change in pH after the dropwise addition, N, N'-methylenebisacrylamide corresponding to 3% by weight is added as a crosslinking agent to the mixed solution of acrylic acid and methacrylic acid already added dropwise, mixed, stirred and dissolved uniformly. A mother aqueous solution is prepared. 300 ml of the monomer mother liquor thus prepared was prepared, and Solution A to which 3 g of sodium persulfate was added was prepared. Separately, 240 ml of pure water was added, 150 g of cement was added thereto, mixed well, and 3 g of triethanolamine was added thereto to prepare a suspension B. The solution A and the suspension B are mixed and stirred at a time.

The results of the gel time measurement, the compressive strength of the homogel and sand gel, the permeability coefficient, and the volume change and compressive strength change after prolonged immersion for the properties of the hydrogel produced through the above examples are shown in Table 1 below. .

* Compressive strength measured up to 20% deformation

* Sand gel is mixed with 500 parts by weight of standard yarn based on 100 parts by weight of chemical

Referring to Table 1, the acrylate-injected drug gel according to the present invention has a relatively low compressive strength of the homogel, but considering that it is used as a ground injection material, the strength of the sand gel is relatively good, especially the permeability coefficient. It can be seen that the impermeability is very excellent.

As described above, the acrylate-injected drug solution according to the present invention has a very low viscosity of 2 centipoise or less except in the case of a combination of cement, which is very injectable and further has a very low permeability coefficient of the resulting gel. In addition, it is easy to control the gel time, so the performance as a ground injection material for the order and index is very excellent, there is a turbid injection effect in the situation and conditions that the conventional grouting method is not effective.

Claims (3)

After preparing an inorganic base aqueous solution, it was neutralized by adding an acrylic acid monomer thereto, and then, N, N'-methylenebisacrylamide was added thereto as a polymerization crosslinking agent to prepare an aqueous acrylate monomer solution. A single catalyst or a mixture of two or more selected from triethanolamine (TEA), diethanolamine (DEA), nitrilo-tris-pripionamide (NTP), and dimethylaminopropionitrile (DMAPN) is added as a reduction catalyst, and Another part of the aqueous acrylate monomer solution is a method of gelling an aqueous solution of acrylate monomers, characterized in that a single or two or more mixtures selected from sodium persulfate and ammonium persulfate are added as an oxidation catalyst and then the two solutions are mixed. After preparing an inorganic base aqueous solution, it was neutralized by adding an acrylic acid monomer thereto, and then, N, N'-methylenebisacrylamide was added thereto as a polymerization crosslinking agent to prepare an acrylate monomer aqueous solution, and triethanolamine was added to the acrylate monomer aqueous solution. (TEA), diethanolamine (DEA), nitrilo-tris-pripionamide (NTP), dimethylaminopropionitrile (DMAPN), or a mixture of two or more selected from the mixture as a reducing catalyst, A method for gelling an aqueous solution of acrylate monomers, comprising adding and dissolving a single or two or more mixtures selected from sodium persulfate and ammonium persulfate with water as an oxidation catalyst and then mixing the two solutions. After preparing an inorganic base aqueous solution, it was neutralized by adding an acrylic acid monomer thereto, and then, N, N'-methylenebisacrylamide was added thereto as a polymerization crosslinking agent to prepare an aqueous acrylate monomer solution, and sodium peroxide was added to the aqueous acrylate monomer solution. A single or a mixture of two or more selected from sulfate, ammonium persulfate is added as an oxidation catalyst and triethanolamine (TEA), diethanolamine (DEA), nitrilo-tris-pripyamide (NTP) in separate pure water. And dimethylaminopropionitrile (DMAPN), a method of gelling an aqueous acrylate monomer, characterized in that the mixture is added and dissolved after the reduction catalyst is mixed with the two solutions.